AI agents call fibonacci to retrieve information from TinyFn without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
| Parameter | Type | Required | Description |
|---|---|---|---|
n | integer | Yes | Position in sequence (0-1000) |
Parameters from the server's own tool schema.
This is a deterministic mathematical utility that only computes and returns data. It performs no write, delete, execute, or financial operations. The tool fits squarely in the Read category as a query-like function that produces output without side effects. Severity is low because misuse by an AI agent would have no harmful consequences—at worst, it generates incorrect or unexpected numeric output.
From the tool's definition The tool name is 'fibonacci' and the description states 'Get the nth Fibonacci number.' This is a pure computational/mathematical function that retrieves or calculates a value without side effects, modification of data, or external operations.
Attacks that exploit this kind of access
Get the nth Fibonacci number. It is categorised as a Read tool in the TinyFn MCP Server, which means it retrieves data without modifying state.
fibonacci accepts 1 parameter: n. Required: n. The full parameter table on this page comes from the server's own tool schema.
Register the TinyFn MCP server in PolicyLayer and add a rule for fibonacci: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches TinyFn. Nothing to install.
fibonacci is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the fibonacci rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for fibonacci. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
fibonacci is provided by the TinyFn MCP server (https://api.tinyfn.io/mcp/all/). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
fibonacci is one line of TinyFn's registry record.
The record carries the whole server: verified identity, auth posture, risk grade, every tool classified, recommended policy — re-checked continuously.
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